1. Field of the Invention
The present invention relates to a substrate processing apparatus and a method of operating a substrate processing apparatus, and more particularly to a substrate processing apparatus and a method of operating a substrate processing apparatus which are useful for polishing a substrate, such as a semiconductor wafer, into a flat mirror surface.
2. Description of the Related Art
A substrate processing apparatus, such as a polishing apparatus, for polishing a surface of a semiconductor wafer into a flat mirror surface, is generally configured to sequentially feed substrates into the apparatus, successively carry out a series of processings for each substrate, and discharge the substrates after the processings out of the apparatus. It is common practice in such an apparatus to stop all the operations for substrates, such as semiconductor wafers, upon the occurrence of a serious failure in the apparatus, and to resume the operations after eliminating the cause of the apparatus failure. It is also common practice to continue sequential feeding of substrates into the apparatus and continue the series of processings for each substrate even upon the occurrence of an apparatus failure if the failure is minor enough to continue the operations of the apparatus.